Electronic device

Abstract

Provided is an electronic device that makes it possible to mount a bridge to a wiring layer with high positional precision.　An electronic device 1 comprises a bridge (31 (31A, 31B)) that electrically connects a plurality of electronic components (20 (20A, 20B, 20C)); and a wiring layer (4) that has wiring, wherein the bridge (31 (31A, 31B)) is metal-bonded to the wiring layer (4). The bridge (31) has bridge wiring (311) that electrically connects the plurality of electronic components (20) to each other.

Description

electronic equipment

[0001] The present invention relates to electronic devices.

[0002] Japanese Patent Application Laid-Open No. 2003-124222 discloses a technique for connecting a plurality of semiconductor chips together using an interconnection chip.

[0003] Special Publication No. 2020-528220

[0004] Prior Art Document 1 does not take into consideration the positional accuracy when fixing the bridge.

[0005] An object of the present invention is to provide an electronic device in which a bridge can be mounted on a wiring layer with high positional accuracy.

[0006] The electronic device according to the present invention comprises a bridge for electrically connecting a plurality of electronic components and a wiring layer having wiring, the bridge being metal-bonded to the wiring layer.

[0007] According to the present invention, it is possible to provide an electronic device in which a bridge can be mounted on a wiring layer with high positional accuracy.

[0008] 1 is a cross-sectional view of an electronic device according to an embodiment of the present invention; FIG. 2 is an exploded cross-sectional view of the electronic device shown in FIG. 1; FIG. 3 is an external view of an electronic device according to an embodiment, viewed from above; FIG. 4 is a diagram showing a manufacturing process for a bridge of an electronic device according to an embodiment, and is a diagram showing a glass substrate preparation process; FIG. 5 is a diagram showing a via filling process for filling a through hole formed in a glass substrate to form a part of a through bridge via; FIG. 6 is a diagram showing an insulating film formation process for forming a bridge insulating layer on a glass substrate; FIG. 7 is a diagram showing a bridge wiring formation process for forming a bridge wiring on a bridge insulating layer; FIG. 8 is a diagram showing an insulating film formation process for forming a bridge insulating layer on a bridge wiring; FIG. 9 is a diagram showing a via filling process for filling an opening formed in a bridge insulating layer to form a through bridge via; FIG. 10 is a diagram showing a bridge wiring formation process; FIG. 11 is a diagram showing a bump electrode formation process; FIG. 12 is a diagram showing a layer stacking process for an electronic device according to an embodiment, and is a diagram showing a release layer formation process for forming a release layer on a panel carrier; FIG. 13 is a diagram showing a wiring formation process for forming a first layer line wiring; FIG. 14 is a diagram showing a wiring layer formation process for forming a wiring layer and an insulating layer; FIG. 15 is a diagram showing a bridge mounting process for mounting a bridge on a wiring layer; FIG. 16 is a diagram showing a resist film formation process; FIG. 17 is a diagram showing a pillar formation process for filling a hole formed in a resist film to form a pillar; FIG. 18 is a diagram showing a resist film removal process for removing the resist film. FIG. 1 is a diagram showing a molding process for covering a bridge and a pillar with an insulating layer; FIG. 2 is a diagram showing a grinding process for grinding the surface of the insulating layer; FIG. 3 is a diagram showing an electrode formation process for forming an electrode from a thin film metal; FIG. 4 is a diagram showing an electronic component mounting process for mounting an electronic component on a connection layer; FIG. 5 is a diagram showing a molding process for covering an electronic component with an insulating layer; FIG. 6 is a diagram showing a grinding process for grinding the surface of the insulating layer; FIG. 7 is a diagram showing a panel carrier removal process for removing a panel carrier; FIG. 8 is a diagram showing a bump electrode formation process for forming a bump electrode on a wiring layer; FIG. 9 is an external view of a bridge according to a modified example of this embodiment viewed from above; FIG. 10 is an external view of a connection layer according to a modified example of this embodiment viewed from above; FIG. 11 is a diagram showing an alignment process in a bridge mounting process for mounting a bridge on a wiring layer; and FIG. 12 is a cross-sectional view of an electronic device according to another embodiment of the present invention.

[0009] Hereinafter, an electronic device 1 according to an embodiment of the present invention will be described with reference to the drawings.

[0010] First, an electronic device 1 according to one embodiment will be described with reference to Figures 1 and 2. Figure 1 is a cross-sectional view of the electronic device 1 according to one embodiment of the present invention. Figure 2 is an exploded cross-sectional view of the electronic device 1 shown in Figure 1. Note that reference numerals for detailed components are omitted in Figure 1.

[0011] 1 and 2, the electronic device 1 according to this embodiment includes an electronic component layer 2, a connection layer 3, and a wiring layer 4 (hereinafter referred to as the "wiring layer 4") serving as a redistribution layer (RDL). The electronic device 1 is mounted on a substrate 5.

[0012] The electronic component layer 2 is formed by covering a plurality of electronic components 20, namely a first electronic component 20A, a second electronic component 20B, and a third electronic component 20C, with an insulating layer 21, which will be described later. The electronic component layer 2 processes data using the electronic components 20. Similarly, the electronic component layer 2 stores data and programs. The electronic component layer 2 executes programs. The electronic component layer 2 performs signal processing. The electronic component layer 2 performs communication. The electronic component layer 2 interfaces with a sensor device.

[0013] In the following description, when there is no need to specify the first electronic component 20A, the second electronic component 20B, and the third electronic component 20C, the first electronic component 20A, the second electronic component 20B, and the third electronic component 20C may be simply referred to as "electronic components 20."

[0014] The connection layer 3 is formed by covering one or more bridges 31 with an insulating layer 30, which will be described later. The connection layer 3 electrically connects the electronic component layer 2 and the wiring layer 4. The connection layer 3 is formed between the electronic component layer 2 and the wiring layer 4. The connection layer 3 may function as a so-called interposer.

[0015] In this embodiment, the multiple bridges 31 include a first bridge 31A and a second bridge 31B. In the following description, when it is not necessary to specify the first bridge 31A and the second bridge 31B, the first bridge 31A and the second bridge 31B may be simply referred to as the "bridge 31."

[0016] The wiring layer 4 transmits signals output from the electronic component layer 2. The wiring layer 4 physically supports the electronic component layer 2 and the connection layer 3. The wiring layer 4 supplies charge to the electronic component layer and / or the connection layer 3. The wiring layer 4 is disposed on the opposite side of the connection layer 3 from the electronic component layer 2. The wiring layer 4 is made up of two or more layers: a layer of signal wiring and ground wiring for signal transmission, and a layer of power wiring and ground wiring for charge supply. From the viewpoint of stable charge supply, it is preferable to provide the power wiring and ground wiring for charge supply in separate layers, in which case the wiring layer 4 will have three or more layers. It is also preferable from the viewpoint of improving transmission signal quality to provide two or more layers of signal wiring and ground wiring for signal transmission, or to provide them in separate layers.

[0017] The substrate 5 physically supports the electronic component layer 2, the connection layer 3, and the wiring layer 4. The substrate 5 functions as a wiring substrate. The substrate 5 is disposed on the opposite side of the wiring layer 4 from the electronic component layer 2 and the connection layer 3. The substrate 5 may be a glass epoxy substrate, or may be a substrate having an insulating layer and a wiring layer provided on a glass base material.

[0018] 1 and 2, the electronic component layer 2 includes a plurality of electronic components 20 and an insulating layer 21. In this embodiment, the plurality of electronic components 20 include a first electronic component 20A, a second electronic component 20B, and a third electronic component 20C.

[0019] The electronic components 20 process data. The electronic components 20 store data and programs. The electronic components 20 execute programs. The electronic components 20 perform signal processing. The electronic components 20 perform communication. The electronic components 20 interface with sensor devices. Each electronic component 20 may perform a different function. The electronic components 20 may be, for example, a logic IC. The electronic components 20 may be, for example, a SoC (System on a Chip). The electronic components 20 may include a memory IC. The electronic components may be, for example, Double Data Rate (DDR), Low-Power Double Data Rate (LPDDR), or High Bandwidth Memory (HBM).

[0020] The electronic components 20 may be arranged such that multiple electronic components 20 are adjacent to one another. That is, a first electronic component 20A, a second electronic component 20B, and a third electronic component 20C may be arranged side by side on the electronic component layer 2. The number of electronic components 20 is not limited to three. The number of electronic components may be two, three or more, or four or more.

[0021] More specifically, the first electronic component 20A and the second electronic component 20B may be arranged adjacent to each other. The second electronic component 20B and the third electronic component 20C may be arranged adjacent to each other. Unless otherwise specified, the following description of the first electronic component 20A and the second electronic component 20B adjacent to each other can also be applied to the nth electronic component and the (n+1)th electronic component adjacent to each other, where n is a natural number.

[0022] By having multiple electronic components 20, the electronic device 1 can process more information and perform more functions than when it has only one electronic component 20. For example, if the number of electronic components 20 is three or more, the electronic device 1 can process more information and perform more functions.

[0023] An integrated circuit (IC) is formed on the electronic component 20. A specific example of the plurality of electronic components 20 is an IC chip (semiconductor chip). The IC chip has semiconductor elements arranged at high density. As an example, the IC chip has a chip substrate, transistors, chip wiring, and a chip insulating layer (not shown).

[0024] The chip substrate is the base of the IC chip. Transistors function as electronic switches, controlling current flow in response to voltage changes. An example of a transistor is a MOSFET (Metal-Oxide-Semiconductor Field-effect Transistor). The chip wiring is the electronic pathway for transmitting signals between transistors and other components. For example, the chip wiring is formed into a fine pattern using conductive metals (such as aluminum or copper). The chip insulating layer prevents short circuits between the chip substrate, transistors, and chip wiring.

[0025] The insulating layer 21 seals the periphery of the electronic component 20, including the transistor. The insulating layer 21 is, for example, an organic insulating layer made of epoxy resin or the like. The organic insulating layer may contain inorganic particles such as silica or alumina. The inclusion of inorganic particles makes it possible to control the linear expansion coefficient and elastic modulus. The insulating layer 21 may be a molding resin. For example, the insulating layer 21 may be formed by transfer molding, in which a pellet-shaped material is heated and softened in a plunger, then the resin is pressed into a mold and cooled to harden and form a desired shape. Alternatively, the insulating layer 21 may be formed by compression molding, in which a liquid or granular molding resin is supplied in advance into an open mold, and the mold is closed to form a molded product under heat and pressure. The insulating layer 21 may be formed by laminating a build-up resin film and then heat-curing it.

[0026] The electronic component 20 has a first opposing portion 200 and an electronic component side electrode 201. On the electronic component side electrode 201, a bump electrode 202 and a bump electrode 203 are formed.

[0027] The first facing portion 200 faces the bridge 31. Specifically, the first facing portion 200 faces the bridge 31 across the insulating layer 21 of the electronic component layer 2. The first facing portion 200 may be a surface facing the bridge 31. Specifically, the first facing portion 200 may be a surface facing the bridge 31 across the insulating layer 21 of the electronic component layer 2. The first facing portion 200 may be the bottom surface of the electronic component 20 when the electronic device 1 shown in FIG. 1 is placed on a horizontal surface.

[0028] The electronic component side electrode 201 is an input / output terminal for current and signals input / output to / from the electronic component 20. The electronic component side electrode 201 is formed on the first opposing portion 200. For example, the electronic component side electrode 201 is formed of copper, a copper-aluminum alloy, tin, a tin-silver alloy, a tin-copper-silver alloy, or a laminate or mixture thereof. The electronic component side electrode 201 is electrically connected to a pillar 32 of the connection layer 3 (described later) via a bump electrode 202. The electronic component side electrode 201 is electrically connected to a bridge 31 of the connection layer 3 (described later) via a bump electrode 203. For example, the bump electrode 203 connected to a bridge electrode 3160 (described later) of a bridge-side first electrode 316 (described later) is a signal line terminal, and the bump electrode 203 connected to a via electrode 3161 (described later) of a bridge-side first electrode 316 (described later) is either a power supply terminal or a ground terminal.

[0029] The bump electrodes 202 and 203 are formed on the electronic component side electrodes 201. As an example, the bump electrodes 202 and 203 are formed from solder. The bump electrodes 202 and 203 may be formed from copper, silver, gold, tin, or alloys thereof. The other bump electrodes described in this embodiment may also be formed from similar materials.

[0030] The connection layer 3 has an insulating layer 30, a bridge 31, and a pillar 32 as a connection layer through-electrode.

[0031] The insulating layer 30 seals the periphery of the bridge 31. The insulating layer 30 is, for example, an organic insulating layer made of epoxy resin or the like. The organic insulating layer may contain inorganic particles such as silica or alumina. The inclusion of inorganic particles makes it possible to control the linear expansion coefficient and elastic modulus. The insulating layer 30 may be a molding resin. For example, the insulating layer 30 may be formed by transfer molding, in which a pellet-shaped material is heated and softened in a plunger, then the resin is pressed into a mold and cooled to harden and form a desired shape. Alternatively, the insulating layer 30 may be formed by compression molding, in which a liquid or granular molding resin is supplied in advance into an open mold, and the mold is closed to form a molded product under heat and pressure. The insulating layer 30 may be formed by laminating a build-up resin film and then heat-hardening it.

[0032] The bridge 31 is electrically connected to the electronic component 20. There may be two or more bridges 31. In this embodiment, the multiple bridges 31 include a first bridge 31A and a second bridge 31B. There may be three or more bridges.

[0033] According to this embodiment, the electronic device 1 can process more information than when there is only one bridge 31 .

[0034] The bridge 31 electrically connects adjacent electronic components 20 to each other. That is, the first bridge 31A (nth bridge) electrically connects adjacent first electronic component 20A (nth electronic component) and second electronic component 20B ((n+1)th electronic component) to each other. Furthermore, the second bridge 31B ((n+1)th bridge) may electrically connect adjacent second electronic component 20B ((n+1)th electronic component) and third electronic component 20C ((n+2)th electronic component) to each other.

[0035] The pillar 32 penetrates the connection layer 3 from a facing portion 33 facing the electronic component layer 2 to a facing portion 34 facing the wiring layer 4, and electrically connects the electronic component 20 to the wiring of the wiring layer 4. The pillar 32 is formed in the insulating layer 30.

[0036] The pillars 32 directly electrically connect the electronic component layer 2 and the wiring layer 4. The pillars 32 are formed by penetrating the insulating layer 30 from the surface facing the electronic component layer 2 (facing portion 33) to the surface facing the wiring layer 4 (facing portion 34). The pillars 32 are formed in a cylindrical shape, and a cavity is formed. A conductor is formed on the inner circumferential surface of the cavity. The cavity may be filled with a conductor. An example of the conductor is copper formed by plating.

[0037] The pillar 32 has an exposed portion as a surface that is exposed at the opposing portion 34 on the wiring layer 4 side. When the connection layer 3 and the wiring layer 4 are joined, the exposed portion of the pillar 32 on the wiring layer 4 side is electrically connected to a third-layer line wiring 46 formed in a fourth opposing portion 40 of the wiring layer 4, which will be described later.

[0038] The pillar 32 has an exposed portion as a surface exposed at the opposing portion 33 on the electronic component layer 2 side. The exposed portion of the pillar 32 on the electronic component layer 2 side may be covered with a pillar electrode 320. The pillar electrode 320 is, for example, a conductive thin film. The pillar electrode 320 is, for example, formed of copper. Note that the exposed portion of the pillar 32 on the electronic component layer 2 side may serve as the pillar electrode 320 without providing a conductive thin film. In the manufacturing process of the electronic device 1, when the electronic component layer 2 is bonded to the connection layer 3, the pillar electrode 320 of the connection layer 3 is electrically connected to the bump electrode 202 of the electronic component layer 2. The pillar 32 is used, for example, as a power line or a ground line of the electronic component 20.

[0039] The bridge 31 includes a substrate 310 made of silicon, ceramics, or glass, a bridge wiring 311 and a bridge insulating layer 312 that form a bridge wiring section, a second opposing section 313, a third opposing section 314, and a bridge through via 315 that serves as a bridge through electrode. The bridge 31 further includes a first bridge-side electrode 316 and a second bridge-side electrode 317.

[0040] The bridge 31 is formed of a substrate 310 selected from silicon, ceramics, and glass. When the substrate 310 is made of glass, it is preferable to use alkali-free glass or quartz glass that does not contain alkali components, from the viewpoint of electrical reliability. It is also preferable to select a substrate 310 having an appropriate linear expansion coefficient and elastic modulus from the viewpoint of reliability in relation to the physical properties of the electronic component layer 2, the connection layer 3, the wiring layer 4, and the substrate 5.

[0041] The relative dielectric constant of silicon is, for example, 12. The relative dielectric constant of alkali-free glass is, for example, 5.8. The relative dielectric constant of quartz glass is, for example, 3.9. Dielectric loss is proportional to the relative dielectric constant. Therefore, the larger the relative dielectric constant, the larger the dielectric loss. Therefore, the bridge 31 that electrically connects multiple electronic components 20 can reduce dielectric loss when the substrate 310 is made of glass compared to when it is made of silicon.

[0042] Dielectric loss has effects on information transmission between multiple electronic components 20, such as signal attenuation, bandwidth limitation, increased delay, and signal distortion, for example.

[0043] Dielectric loss absorbs and attenuates the signal energy, resulting in a loss of signal quality as the signal travels down the wire. Signal attenuation is a factor that limits the distance information can be transmitted.

[0044] In wiring with high dielectric loss, the frequency components of a signal attenuate more quickly, which can limit the bandwidth. In wiring with high dielectric loss, high-frequency signals are more likely to degrade along the transmission path, which can affect high-speed data communications.

[0045] Wiring with high dielectric loss can slow signal transmission because it takes longer for the signal to replenish the energy absorbed within the wiring. Longer signal delays result in less reliable communication.

[0046] Dielectric losses can cause signals to become distorted during transmission. High dielectric losses affect the amplitude, phase, and waveform of the signal, reducing its accuracy.

[0047] The bridge wiring 311 electrically connects the plurality of electronic devices 1 to one another. The bridge wiring 311 is, for example, a copper wiring.

[0048] According to this embodiment, the plurality of electronic components 20 arranged on the electronic component layer 2 can directly exchange power and information with each other via the bridge wiring 311 .

[0049] The bridge insulating layer 312 insulates the bridge wiring 311 .

[0050] By providing the bridge insulating layer 312, it is possible to suppress the occurrence of short circuits between the plurality of bridge wirings 311 and between the bridge wirings 311 and the through-bridge vias 315.

[0051] The bridge insulating layer 312 seals the bridge wiring 311. The bridge insulating layer 312 is formed on the electronic component layer 2 side of the glass base material 310, that is, in the vicinity of the second opposing portion 313.

[0052] In this embodiment, multiple bridge insulating layers 312 are stacked to sandwich the bridge wiring 311. The bridge wiring section may be formed as a multi-layer wiring structure having multiple layers of bridge wiring 311. The multi-layer wiring structure has multiple layers of bridge insulating layers 312 and multiple layers of bridge wiring 311, and the bridge insulating layers 312 and bridge wiring 311 are stacked alternately. This allows signals to be transmitted between multiple electronic components 20 using a large number of wirings. This allows the density of the electronic components 20 and the wiring to be improved. The bridge wiring 311 may be disposed directly on the glass substrate 310. The bridge wiring 311 may also be disposed on the outermost surface of the bridge 31.

[0053] The bridge wiring portion made up of the bridge insulating layer 312 and the bridge wiring 311 may also be formed on the wiring layer 4 side of the glass substrate 310, i.e., near the third opposing portion 314. In this case, a via is formed in the bridge 31 to electrically connect the bridge-side first electrode 316 formed on the second opposing portion 313 of the bridge 31 to the bridge wiring 311 formed near the third opposing portion 314. This also makes it possible to improve the density of the electronic components 20 and the wiring.

[0054] The bridge insulating layer 312 may be an organic insulating layer. For example, the bridge insulating layer 312 may be made of a resin material such as a photosensitive resin material or a non-photosensitive resin material, such as a polyimide resin. Organic insulating layers formed from resin materials generally have a low dielectric constant. Therefore, using an organic insulating layer as the bridge insulating layer 312 can further reduce dielectric loss. Furthermore, by using an organic insulating layer, the bridge insulating layer 312 can also be made thicker as the bridge wiring 311 is made thicker. Even in this case, manufacturing costs can be reduced. Increasing the thickness of the bridge wiring 311 is effective in reducing the conductor resistance of the wiring. The organic insulating layer is formed, for example, by spin coating. The dielectric constant of the organic insulating layer may be lower than that of silicon. The dielectric constant of the organic insulating layer may be lower than that of the glass material constituting the glass substrate 310. The dielectric constant of the organic insulating layer is preferably 10 or less, and more preferably 5 or less.

[0055] The bridge insulating layer 312 may be an inorganic insulating layer. For example, the bridge insulating layer 312 may be made of silicon dioxide (SiO ２ The inorganic insulating layer such as silicon dioxide is formed by, for example, chemical vapor deposition (CVD).

[0056] The second facing portion 313 of the bridge 31 faces the first facing portion 200 of each of the plurality of electronic components 20. That is, the second facing portion 313 faces the first facing portion 200 of each of the first electronic component 20A, the second electronic component 20B, and the third electronic component 20C. The second facing portion 313 may be the upper surface of the bridge 31 when the electronic device 1 shown in FIG. 1 is placed on a horizontal surface.

[0057] The first opposing portion 200 and the second opposing portion 313 are electrically connected. Specifically, the first opposing portion 200 of the first electronic component 20A is electrically connected to the bridge-side first electrode 316 formed on the second opposing portion 313 of the bridge 31 via the bump electrode 203. The first opposing portion 200 of the second electronic component 20B is electrically connected to the bridge-side first electrode 316 formed on the second opposing portion 313 of the bridge 31 via the bump electrode 203. The first opposing portion 200 of the first electronic component 20A is electrically connected to the pillar electrode 320 formed on the opposing portion 33 on the electronic component layer 2 side of the connection layer 3 via the bump electrode 202.

[0058] The third opposing portion 314 of the bridge 31 is formed on the opposite side of the bridge 31 from the second opposing portion 313 of the bridge 31. The third opposing portion 314 faces the wiring layer 4. Specifically, the third opposing portion 314 faces the wiring layer 4 via the insulating layer 30. The third opposing portion 314 may be the lower surface of the bridge 31 when the electronic device 1 shown in FIG. 1 is placed on a horizontal surface.

[0059] More specifically, when the electronic device 1 according to this embodiment is placed on a horizontal surface, the bridge wiring 311 is formed to extend horizontally inside the bridge insulating layer 312, and further bends at both horizontal ends toward the electronic component 20 side of the electronic component layer 2 and extends to be exposed at the second opposing portion 313. Here, the horizontal direction is the direction parallel to the surface of the second opposing portion 313.

[0060] In other words, when the electronic device 1 according to this embodiment is placed on a horizontal surface, the bridge wiring 311 is formed so as to extend inside the bridge insulating layer 312 from the vertically lower portion of the first electronic component 20A to the vertically lower portion of the second electronic component 20B. The bridge wiring 311 is formed so as to bend at the end on the first electronic component 20A side and extend until it is exposed at the second opposing portion 313. The bridge wiring 311 is formed so as to bend at the end on the second electronic component 20B side and extend until it is exposed at the second opposing portion 313.

[0061] The current and information output from the first electronic component 20A are transmitted from the bump electrode 203 of the electronic component-side electrode 201 to the bridge wiring 311 via a bridge electrode 3160 (described later) of the bridge-side first electrode 316 formed on the first electronic component 20A side of the bridge 31. The second electronic component 20B receives the current and information transmitted to the bridge wiring 311 from the bridge electrode 3160 of the bridge-side first electrode 316 formed on the second electronic component 20B side of the bridge 31 via the bump electrode 203 of the electronic component-side electrode 201 of the second electronic component 20B.

[0062] Similarly, the current and information output from the second electronic component 20B are transmitted from the bump electrode 203 of the electronic component-side electrode 201 to the bridge wiring 311 via the bridge electrode 3160 of the bridge-side first electrode 316 formed on the second electronic component 20B side of the bridge 31. The first electronic component 20A receives the current and information transmitted to the bridge wiring 311 from the bridge electrode 3160 of the bridge-side first electrode 316 formed on the first electronic component 20A side of the bridge 31 via the bump electrode 203 of the electronic component-side electrode 201 of the first electronic component 20A.

[0063] The bridge through via 315 directly electrically connects the electronic component layer 2 and the wiring layer 4. The bridge through via 315 is formed to penetrate from the second opposing portion 313 opposing the electronic component layer 2 to the third opposing portion 314 opposing the wiring layer 4. The bridge through via 315 is formed in a cylindrical shape, and a cavity is formed. A conductor is formed on the inner peripheral surface of the cavity. The cavity may be filled with a conductor. One example of the conductor is copper formed by a plating method. It is preferable that the multiple bridge through vias 315 have a via diameter of 15 μm or less and are formed at a pitch of 25 μm or more and 100 μm or less. Within this range, the bridge through vias 315 are likely to maintain high strength while increasing the bridge density.

[0064] The bridge through via 315 is preferably a linear straight via electrode that penetrates from the second opposing portion 313 to the third opposing portion 314. That is, the bridge through via 315 is preferably a straight via electrode that penetrates the glass substrate 310 and the bridge insulating layer 312 in a linear manner. This allows the wiring length to be shortened when electrically connecting the electronic component 20 and the wiring layer 4 via the bridge 31. This configuration is particularly effective when an HBM is used as the electronic component 20. In an HBM, signal line contacts are densely arranged, and power line contacts and ground line contacts are also arranged near these areas. As a specific example, the power line of the electronic component 20 and the power line of the wiring layer 4 are connected via the bridge through via 315, thereby shortening the connection distance between them. Furthermore, the ground line of the electronic component 20 and the ground line of the wiring layer 4 are connected via the bridge through via 315, thereby shortening the connection distance between them. Even in such a case, the bridge wiring 311 can be used as a signal line to electrically connect multiple electronic components 20 to each other with a short wiring length, while the bridge through via 315 can be used as a power line or ground line to electrically connect the electronic components 20 to the wiring layer 4 with a short wiring length.

[0065] A bridge-side first electrode 316 is formed on the second opposing portion 313. That is, the bridge-side first electrode 316 is formed on the second opposing portion 313 of the bridge 31. The bridge-side first electrode 316 is electrically connected to the bump electrode 203 of the electronic component 20 on the electronic component layer 2.

[0066] The first bridge-side electrode 316 includes a bridge electrode 3160 and a via electrode 3161 .

[0067] The bridge electrode 3160 is configured, for example, by a conductive thin film that electrically conductively covers an exposed portion of the bridge wiring 311, which is sealed in the bridge insulating layer 312, extending toward the electronic component 20 and serving as a surface exposed to the second opposing portion 313. The bridge electrode 3160 is formed of copper, for example. Note that the exposed portion of the bridge wiring 311 on the second opposing portion 313 side may serve as the bridge electrode 3160 without providing a conductive thin film.

[0068] The via electrode 3161 is configured, for example, by a conductive thin film that extends from the bridge through via 315 toward the electronic component 20 and covers an exposed portion serving as a surface exposed to the third opposing portion 314. The via electrode 3161 is formed, for example, from copper. Note that the exposed portion of the bridge wiring 311 on the second opposing portion 313 side may be used as the via electrode 3161 without providing a conductive thin film.

[0069] A bridge-side second electrode 317 is formed on the third opposing portion 314. That is, the bridge-side second electrode 317 is formed on the third opposing portion 314 of the bridge 31. The bridge-side second electrode 317 is electrically connected to the third-layer line wiring 46 of the wiring layer 4.

[0070] The bridge-side second electrode 317 includes a via electrode 3170 and a bump electrode 3171. The bump electrode 3171 may have a structure in which a solder material is formed on the tip of a copper pillar, and preferably the solder contains tin and bismuth.

[0071] The via electrode 3170 is configured, for example, by a conductive thin film that extends from the bridge through via 315 toward the wiring layer 4 and covers an exposed portion serving as a surface exposed to the third opposing portion 314. The via electrode 3170 is formed, for example, from copper. Note that the exposed portion of the bridge wiring 311 on the third opposing portion 314 side may be used as the via electrode 3170 without providing a conductive thin film.

[0072] A bump electrode 3171 is formed on the via electrode 3170. The bump electrode 3171 is connected to either the power supply line or the ground line of the wiring layer 4.

[0073] <Wiring layer> The wiring layer 4 has a fourth opposing portion 40, a fifth opposing portion 41, a first-layer line wiring 42, a first insulating layer 43, a second-layer line wiring 44, a second insulating layer 45, a third-layer line wiring 46, a first-layer via wiring 47, a second-layer via wiring 48, and a bump electrode 49.

[0074] The fourth opposing portion 40 faces the third opposing portion 314 of the bridge 31. Specifically, the fourth opposing portion 40 faces the bridge 31 across the insulating layer 30 of the connection layer 3. The fourth opposing portion 40 may be a surface facing the bridge 31. The fourth opposing portion 40 may be a surface facing the bridge 31 across the insulating layer 30 of the connection layer 3. The fourth opposing portion 40 may be the upper surface of the wiring layer 4 when the electronic device 1 shown in FIG. 1 is placed on a horizontal surface.

[0075] The fourth opposing portion 40 of the wiring layer 4 and the third opposing portion 314 of the bridge 31 of the connection layer 3 are electrically connected. Specifically, the third-layer line wiring 46 of the fourth opposing portion 40 of the wiring layer 4 is electrically connected to the via electrode 3170 formed in the bridge 31 of the connection layer 3. The via electrode 3170 of the bridge-side second electrode 317 formed on the first electronic component 20A side is electrically connected to the third-layer line wiring 46 of the wiring layer 4. The via electrode 3170 of the bridge-side second electrode 317 formed on the second electronic component 20B side is electrically connected to the third-layer line wiring 46 of the wiring layer 4. At this time, the bridge 31 is metal-bonded to the wiring layer 4 by flip-chip mounting. This allows the bridge 31 to be mounted with extremely high positioning accuracy.

[0076] The fifth opposing portion 41 is formed on the wiring layer 4 on the opposite side to the fourth opposing portion 40 of the wiring layer 4. The fifth opposing portion 41 faces the substrate 5. Specifically, the fifth opposing portion 41 faces the substrate 5 via a bump electrode 49 formed on the fifth opposing portion 41. The fifth opposing portion 41 may be the lower surface of the wiring layer 4 when the electronic device 1 shown in FIG. 1 is placed on a horizontal surface.

[0077] The first-layer line wiring 42 is formed in the fifth opposing portion 41 of the wiring layer 4. The first-layer line wiring 42 may be formed of copper wiring, for example.

[0078] The first insulating layer 43 insulates the first-layer line wiring 42, the first-layer via wiring 47, and the second-layer line wiring 44. The first insulating layer 43 is formed above the first-layer line wiring 42 when the electronic device 1 shown in FIG. 1 is placed on a horizontal surface. The first insulating layer 43 may be formed, for example, from a resin such as polyimide, polybenzoxazole, or benzocyclobutene. If these resins have photosensitive properties, vias (openings) can be formed by photolithography and filled with a conductive material such as metal to electrically connect the wiring layers formed above and below the resin material. If the resin material is not photosensitive, via openings can also be formed by laser light irradiation or dry etching.

[0079] The second-layer line wiring 44 is laminated on the first insulating layer 43 on the side opposite to the first-layer line wiring 42. The second-layer line wiring 44 is formed to improve the density of the electronic components 20 and the wiring when a plurality of electronic components 20 are mounted in the electronic device 1 according to this embodiment. The second-layer line wiring 44 is laminated on top of the first insulating layer 43 when the electronic device 1 shown in FIG. 1 is placed on a horizontal surface. The second-layer line wiring 44 may be formed from the same composition as the first-layer line wiring 42.

[0080] The second insulating layer 45 insulates the second-layer line wiring 44, the second-layer via wiring 48, and the third-layer line wiring 46. The second insulating layer 45 is laminated on top of the second-layer line wiring 44 when the electronic device 1 shown in FIG. 1 is placed on a horizontal surface. The second insulating layer 45 can be formed from the same composition as the first insulating layer 43.

[0081] The third-layer line wiring 46 is formed in the fourth opposing portion 40 of the wiring layer 4. When the connection layer 3 and the wiring layer 4 are joined, the third-layer line wiring 46 is electrically connected to the exposed portion of the pillar 32 formed in the connection layer 3 on the wiring layer 4 side. When the connection layer 3 and the wiring layer 4 are joined, the third-layer line wiring 46 is electrically connected to the bridge-side second electrode 317 of the bridge 31. The third-layer line wiring 46 is laminated on top of the second insulating layer 45 when the electronic device 1 shown in FIG. 1 is placed on a horizontal surface. The third-layer line wiring 46 can be formed of the same composition as the first-layer line wiring 42 and the second-layer line wiring 44.

[0082] The first-layer via wiring 47 electrically connects the first-layer line wiring 42 and the second-layer line wiring 44. When the electronic device 1 shown in FIG. 1 is placed on a horizontal surface, the first-layer via wiring 47 is formed to extend vertically from the first-layer line wiring 42 to the second-layer line wiring 44.

[0083] The second-layer via wiring 48 electrically connects the second-layer line wiring 44 and the third-layer line wiring 46. When the electronic device 1 shown in FIG. 1 is placed on a horizontal surface, the second-layer via wiring 48 is formed to extend vertically from the second-layer line wiring 44 to the third-layer line wiring 46.

[0084] The bump electrode 49 electrically connects the wiring layer 4 and the substrate 5. When the wiring layer 4 and the substrate 5 are joined, the bump electrode 49 electrically connects the first-layer line wiring 42 of the wiring layer 4 and wiring (not shown) of the substrate 5. The bump electrode 49 is formed on the fifth opposing portion 41.

[0085] <Overlapping of Electronic Component and Bridge> Next, the electronic device 1 according to this embodiment will be described with reference to Fig. 3 in addition to Fig. 1 and Fig. 2. Fig. 3 is an external view of the electronic device 1 according to this embodiment as viewed from above.

[0086] FIG. 3 shows a first electronic component 20A, a second electronic component 20B, a third electronic component 20C, a first bridge 31A, and a second bridge 31B that are included in the electronic device 1 according to this embodiment.

[0087] As shown in Figure 3, when the electronic device 1 of this embodiment is placed on a horizontal surface and the electronic component layer 2 and the connection layer 3 are viewed in the stacking direction, the bridge 31 is positioned so as to overlap each of the multiple electronic components 20.

[0088] According to this embodiment, the electronic components 20 can be densely arranged on the electronic component layer 2. Therefore, in an electronic device 1 of a specified size, the amount of information that can be processed by the electronic components 20 can be increased.

[0089] In other words, when the electronic device 1 according to this embodiment is placed on a horizontal surface and viewed vertically from above, a portion of the first electronic component 20A overlaps a portion of the first bridge 31A. Similarly, a portion of the second electronic component 20B overlaps a portion of the first bridge 31A. Similarly, a portion of the second electronic component 20B overlaps a portion of the second bridge 31B. Similarly, a portion of the third electronic component 20C overlaps a portion of the second bridge 31B.

[0090] 2 , when the electronic device 1 according to this embodiment is placed on a horizontal surface and viewed vertically from above, the electronic component-side electrode 201 of the first electronic component 20A overlaps with the bridge-side first electrode 316 of the first bridge 31A. Similarly, the electronic component-side electrode 201 of the second electronic component 20B overlaps with the bridge-side first electrode 316 of the first bridge 31A. Similarly, the electronic component-side electrode 201 of the second electronic component 20B overlaps with the bridge-side first electrode 316 of the second bridge. Similarly, the electronic component-side electrode 201 of the third electronic component 20C overlaps with the bridge-side first electrode 316 of the second bridge 31B. The same applies below.

[0091] 1 , when the electronic component layer 2 and the connection layer 3 are joined, the bump electrode 203 of the electronic component-side electrode 201 of the first electronic component 20A is electrically connected to the bridge electrode 3160 and the via electrode 3161 of the bridge-side first electrode 316 of the first bridge 31A. Similarly, the bump electrode 203 of the electronic component-side electrode 201 of the second electronic component 20B is electrically connected to the bridge electrode 3160 and the via electrode 3161 of the bridge-side first electrode 316 of the first bridge 31A.

[0092] Solder can be used to connect the electrodes of the electronic component 20 and the connection layer 3. The solder preferably contains tin and silver as its main component. When connecting the electronic component to the connection layer 3 after connecting the bridge to the wiring layer 4, the soldered connection between the bridge and the wiring layer 4 is also heated to a considerable extent during the process of connecting the electronic component to the connection layer 3. If the solder connecting the bridge and the wiring layer 4 melts, the bridge may become misaligned. By using a solder composition that contains tin and bismuth to connect the bridge and the wiring layer and converting this portion into an intermetallic compound after the solder connection, the melting point of this portion can be made much higher than the melting point of a solder containing tin and silver as its main component. This is preferable because, when soldering the electronic component to the connection layer 3, the solder connecting the bridge and the wiring layer 4 does not melt, thereby preventing any adverse effects on the bridge placement accuracy.

[0093] The bridge 31 may be smaller than any of the multiple electronic components 20 connected to it. Specifically, the first bridge 31A is smaller than the first electronic component 20A and smaller than the second electronic component 20B. For example, when the electronic device 1 according to this embodiment is placed on a horizontal surface and the electronic component layer 2 and the connection layer 3 are viewed in the stacking direction, the area of ​​the first bridge 31A is smaller than the area of ​​the first electronic component 20A and the area of ​​the second electronic component 20B. In other words, the area of ​​the first bridge 31A in plan view is smaller than both the area of ​​the first electronic component 20A and the area of ​​the second electronic component 20B in plan view.

[0094] According to this embodiment, the proportion of the bridge 31 using the glass base material 310 in the wiring layer 4 can be reduced, and therefore an increase in costs can be suppressed.

[0095] <Bridge Manufacturing Process> Next, a manufacturing process of the electronic device 1 according to this embodiment will be described with reference to Figures 4A to 4H. Figures 4A to 4H are views showing manufacturing processes for the bridge 31 of the electronic device 1 according to one embodiment.

[0096] 4A is a diagram showing a glass substrate preparation step for preparing a glass substrate 310. As shown in FIG. 4A, first, the glass substrate 310 is prepared. The glass substrate 310 is, for example, a glass wafer. In practice, after the steps shown in FIG. 4H are completed, the glass substrate 310 is cut into chips by dicing to the size of one bridge 31. However, for the sake of convenience, FIGS. 4A to 4H will be described using a glass substrate 310 the size of one bridge 31.

[0097] FIG. 4B illustrates a via filling process for forming a portion of a bridge through via 315 by filling the formed through hole after the through hole forming process for forming a through hole in the glass substrate 310. As shown in FIG. 4B , a through hole is formed so as to penetrate from the first main surface 310A to the second main surface 310B (the third opposing portion 314 of the bridge 31) of the glass substrate 310. The through hole is formed, for example, by laser processing. After the laser processing, it is also preferable to smooth the surface of the through hole by etching with hydrofluoric acid. The through hole is formed by forming a seed layer by sputtering film formation or electroless plating, and then forming a metal such as copper on the seed layer by electroplating, thereby performing a conductive process to reduce resistance. A metal layer may be formed only on the inner wall surface of the through hole, or the entire hole may be filled with metal. This forms a via electrode as at least a portion of the bridge through via 315.

[0098] 4C is a diagram showing an insulating film formation step in which a bridge insulating layer 312 is formed on the first main surface 310A of the glass substrate 310. As shown in FIG. 4C, the bridge insulating layer 312 is formed on the first main surface 310A of the glass substrate 310. The bridge insulating layer 312 is formed by depositing an organic insulating layer by, for example, spin coating. Examples of materials that can be used for the organic insulating film layer include polyimide, polybenzoxazole, and benzocyclobutene. Alternatively, SiO ２ The insulating layer is formed by depositing an inorganic insulating layer such as the above.

[0099] FIG. 4D is a diagram showing a bridge wiring formation process in which a bridge wiring 311 is formed on the bridge insulating layer 312. As shown in FIG. 4D , a bridge wiring 311 is further formed on the bridge insulating layer 312 on the first main surface 310A side of the glass substrate 310. The bridge wiring 311 is formed, for example, by an additive method. An example of the additive method is to form a resist on the bridge insulating layer 312 and then form the bridge wiring 311 by electroless plating (full additive method). Other methods include forming a seed layer made of titanium or copper by sputtering, forming a wiring pattern with resist, and then forming metal wiring such as copper by electrolytic plating, and then peeling the resist and etching away the seed layer between the wiring to form wiring (semi-additive method), or using a damascene process. For example, copper wiring is used as the bridge wiring 311.

[0100] 4E is a diagram showing an insulating film formation step in which a bridge insulating layer 312 is formed on the bridge wiring 311. As shown in FIG. 4E, a bridge insulating layer 312 is further formed on the bridge wiring 311 laminated on the bridge insulating layer 312, and the bridge wiring 311 is sealed with the bridge insulating layer 312. Note that the steps of FIG. 4D and FIG. 4E may be repeated to form a bridge wiring section with a multilayer wiring structure having multiple layers of bridge wiring 311. In this case, the bridge wiring section has multiple layers of bridge insulating layers 312 and multiple layers of bridge wiring 311, and the bridge insulating layers 312 and bridge wiring 311 are laminated alternately. This enables signal transmission between multiple electronic components 20 using a large number of wirings.

[0101] When the number of signal lines between electronic components interconnected by the bridge wiring increases, the wiring width narrows and the number of wiring layers increases. For example, if the width of the bridge wiring and the spacing between the wiring are both 2 μm, the number of bridge wiring layers may become six or more for 1024 bits.

[0102] FIG. 4F illustrates a via filling process for forming a through-bridge via 315 by filling the formed opening in the bridge insulating layer 312. If the resin material constituting the bridge insulating layer 312 has a photosensitive function, a via (opening) is formed by photolithography and filled with a conductive material such as metal. The conductive material is connected to a via electrode (not shown) of the glass substrate 310, thereby forming the through-bridge via 315. If the resin material is not photosensitive, the via opening can also be formed by laser light irradiation or dry etching. For example, after forming the via (opening), a seed layer is first formed on the inner surface of the via by sputtering. A titanium film, for example, is used as the seed layer. Then, the via is filled by electrolytic plating to form the through-bridge via 315. The via electrode serving as the through-bridge via 315 is formed of, for example, copper. After this, the surface of the bridge 31 is polished by CMP to remove excess metal formed during the via filling process. The surface on the first main surface 310A side polished by CMP becomes the second opposing portion 313 of the bridge 31. The second main surface 310B of the glass substrate 310 becomes the third opposing portion 314 of the bridge 31.

[0103] 4G is a diagram showing the bridge wiring formation step. As shown in FIG. 4G, the bridge wiring 311 is additionally formed so that the bridge wiring 311 is exposed from the second opposing portion 313. This additional wiring is formed by, for example, a damascene method or a semi-additive method. As a result, the bridge wiring 311 is formed so that it is bent at both horizontal ends and has its ends exposed at the second opposing portion 313.

[0104] 4H is a diagram showing the bump electrode formation step. As shown in FIG. 4H , a bridge-side second electrode 317 is formed on the third opposing portion 314 side of the through bridge via 315. That is, a via electrode 3170 is formed as a seed layer on the exposed portion of the through bridge via 315 on the third opposing portion 314 side, and a bump electrode 3171 is further formed on the via electrode 3170. Note that the formation of the seed layer may be omitted. Thereafter, the substrate is cut to chip size by dicing, and the bridge 31 on which the bump electrode is formed is completed.

[0105] <Laminating Process of Electronic Device> Next, the laminating process of the electronic device 1 according to one embodiment will be described with reference to Figures 5A to 5O. Figures 5A to 5O are views showing the laminating process of the electronic device 1 according to one embodiment.

[0106] FIG. 5A illustrates a release layer formation process in which a release layer 102 is formed on the panel carrier 100 prepared in the panel carrier preparation process. As shown in FIG. 5A , the release layer 102 is formed on the base panel carrier 100. Materials such as glass, ceramics such as alumina, and silicon can be preferably used for the panel carrier. Glass carriers are preferred because they have a wide range of linear expansion coefficients, and using an appropriate linear expansion coefficient can limit the range of warping during the process. Ceramic carriers are preferred because they have a high elastic modulus, which makes it easy to suppress warping after the formation of the wiring layer and the molding material. Silicon carriers are preferred because their high elastic modulus makes them effective in suppressing warping during the process, and they facilitate the formation of fine wiring.

[0107] 5B is a diagram showing a wiring formation process for forming first-layer line wiring 42 on release layer 102. As shown in Fig. 5B, a copper layer is formed on release layer 102 to form first-layer line wiring 42. The patterned first-layer line wiring 42 is formed by, for example, a damascene method or a semi-additive method.

[0108] 5C is a diagram showing a wiring layer forming step of forming the wiring layer 4 on the release layer 102. As shown in FIG.

[0109] For example, the wiring layer 4 is formed by laminating a first insulating layer 43, a second-layer line wiring 44, a second insulating layer 45, and a third-layer line wiring 46 in this order on the first-layer line wiring 42. The first-layer via wiring 47 may be formed after the first insulating layer 43 is formed. The second-layer via wiring 48 may be formed after the second insulating layer 45 is formed.

[0110] 5D is a diagram showing a bridge mounting process for mounting the bridge 31 on the wiring layer 4. As shown in FIG. 5D, the bridge 31 (first bridge 31A, second bridge 31B) fabricated by the processes shown in FIGS. 4A to 4H is mounted on the wiring layer 4. At this time, the bridge 31 is metal-bonded to the wiring layer 4 by flip-chip mounting. More specifically, the bridge-side second electrode 317 of the bridge 31 is metal-bonded to a contact portion of the third-layer line wiring 46 of the wiring layer 4. This allows the bridge 31 to be mounted with extremely high positioning accuracy.

[0111] 5E is a diagram illustrating a resist film formation step, which is part of the pillar formation step. As shown in FIG. 5E, a thick resist film 104 is formed so as to cover the bridges 31 (first bridges 31A and second bridges 31B).

[0112] 5F is a diagram showing a pillar formation process in which, after the hole formation process in which holes are formed in the resist film 104, vias are filled in the formed holes to form pillars 32. As shown in FIG. 5F , holes are formed by etching predetermined locations (contact portions of the third-layer line wiring 46) of the resist film 104, and then the formed holes are filled with vias by electrolytic plating to form the pillars 32. As an example of via filling, a seed layer is first formed on the inner surface of the hole by sputtering. A titanium film, for example, is used as the seed layer. Then, the vias are filled by electrolytic plating to form the pillars 32. The metal pillars serving as the pillars 32 are formed of, for example, copper.

[0113] Regarding the order of mounting the bridge and forming the pillar, the following steps may be performed in this order on the wiring layer 4 before mounting the bridge: applying resist, forming holes in the resist using lithography or the like, forming a seed layer by sputtering, forming pillars by electrolytic plating, and removing the resist, to form the pillars, and then mounting the bridge, etc.

[0114] 5G is a diagram showing a resist film removal step of removing the resist film 104. As shown in FIG. 5G, the resist film 104 is removed to expose the bridges 31 (first bridges 31A and second bridges 31B) and the pillars 32.

[0115] 5H is a diagram showing a molding step in which the bridges 31 and pillars 32 are covered with the insulating layer 30. As shown in FIG. 5H , the bridges 31 (first bridges 31A and second bridges 31B) and pillars 32 are molded with the insulating layer 30. Before molding with the insulating layer 30, the spaces between the bridges 31 and the wiring layer 4 may be sealed with a capillary flow underfill material, and molding may then be performed. However, it is preferable to perform a mold underfill step in which the spaces between the bridges 31 and the wiring layer 4 are also sealed together during the molding step in which the periphery of the bridge is covered, as this simplifies the process.

[0116] 5I is a diagram showing a grinding step for grinding the surface of the insulating layer 30. As shown in FIG. 5I, the surface of the insulating layer 30 is ground with a grinder or the like to expose the second opposing portion 313 of the bridge 31. At this time, the pillar 32 is also ground to form an exposed portion of the pillar 32 on the opposing portion 33 side of the connection layer 3 on the electronic component layer 2 side.

[0117] 5J is a diagram showing an electrode formation process for forming electrodes made of thin-film metal. As shown in FIG. 5J, a bridge electrode 3160 made of thin-film metal is formed on the surface of the bridge wiring 311 exposed at the second opposing portion 313 of the bridge 31 (first bridge 31A, second bridge 31B), and a via electrode 3161 made of thin-film metal is formed on the surface of the through-bridge via 315. Furthermore, a pillar electrode 320 made of thin-film metal is formed on the surface of the pillar 32. However, this process is not necessarily required, and the exposed surfaces of the bridge wiring 311, the through-bridge via 315, and the pillar 32 may be used as electrodes as they are. In this way, the connection layer 3 is formed.

[0118] 5K is a diagram showing an electronic component mounting process for mounting electronic components 20 on the connection layer 3. As shown in FIG. 5K, electronic components 20 (first electronic component 20A, second electronic component 20B, third electronic component 20C) are mounted on the connection layer 3 so as to overlap portions of bridges 31 (first bridge 31A, second bridge 31B). Specifically, bump electrodes 203 and bump electrodes 202 of the electronic components 20 (first electronic component 20A, second electronic component 20B, third electronic component 20C) are bonded to bridges 31 (first bridge 31A, second bridge 31B) and pillars 32. At this time, electronic components 20 are metal-bonded to connection layer 3 by flip-chip mounting. This allows electronic components 20 to be mounted with extremely high positioning accuracy.

[0119] 5L is a diagram showing a molding process for covering electronic components 20 with insulating layer 21. As shown in FIG. 5L, electronic components 20 (first electronic component 20A, second electronic component 20B, third electronic component 20C) are molded with insulating layer 21.

[0120] 5M is a diagram showing a grinding step for grinding the surface of insulating layer 21. As shown in Fig. 5M, insulating layer 21 is ground using a grinder or the like to expose the surfaces of electronic components 20 (first electronic component 20A, second electronic component 20B, third electronic component 20C). This step is not necessarily required, but is useful when a heat dissipation structure is formed directly on electronic component 20 for heat dissipation.

[0121] Fig. 5N is a diagram showing a panel carrier removal step for removing the panel carrier 100. As shown in Fig. 5N, the panel carrier 100 and the release layer 102 are removed.

[0122] 5O is a diagram showing a bump electrode formation process for forming bump electrodes 49 on the wiring layer 4. As shown in FIG. 5O, the bump electrodes 49 are formed on the first-layer line wiring 42 of the wiring layer 4. This completes the electronic device 1. Thereafter, the electronic device 1 is mounted on the substrate 5 using the bump electrodes 49.

[0123] Next, Fig. 6A to Fig. 6C show modified examples of this embodiment. Fig. 6A is an external view of the bridge 31 of the modified example as viewed from above (planar view). Fig. 6B is an external view of the wiring layer 4 as viewed from above (planar view). Fig. 6C is a diagram showing an alignment step in the bridge mounting step of mounting the bridge 31 on the wiring layer 4. Note that the third-layer line wiring 46 is not shown in Figs. 6B and 6C.

[0124] As shown in FIG. 6A, the bridge 31 has a first alignment mark 50A as an alignment mark.

[0125] In this modification, the first alignment mark 50A is arranged near the second opposing portion 313 (see FIG. 4H ). The first alignment mark 50A is arranged, for example, in the bridge insulating layer 312. Specifically, the first alignment mark 50A may be arranged on the same layer as the layer on which the bridge wiring 311 is arranged. The first alignment mark 50A may be made of the same material as the bridge wiring 311. This simplifies the process of forming the alignment mark. However, the first alignment mark 50A may be arranged on a layer different from the layer on which the bridge wiring 311 is arranged. The first alignment mark 50A may be made of a material different from that of the bridge wiring 311.

[0126] The first alignment mark 50A is arranged in the same layer as the bridge wiring 311, but spaced apart from the bridge wiring 311. In this way, the first alignment mark 50A is provided separately from the bridge wiring 311, thereby enabling more accurate alignment. However, a part of the bridge wiring 311 may also serve as the first alignment mark 50A.

[0127] The first alignment mark 50A has a shape corresponding to a second alignment mark 50B disposed on the wiring layer 4, which will be described later. The first alignment mark 50A is, for example, a cross-shaped mark, although the shape is not limited to this.

[0128] It is preferable that a plurality of first alignment marks 50A are provided, and more preferably three or more are provided. In this modified example, three first alignment marks 50A are provided.

[0129] The first alignment mark 50A may be disposed on the surface of the second opposing portion 313 (see FIG. 4H ). The first alignment mark 50A may be disposed on the bridge insulating layer 312. The first alignment mark 50A may also be disposed on the glass substrate 310 on the second opposing portion 313 side.

[0130] The first alignment mark 50A may be arranged near the third opposing portion 314 (see FIG. 4H ). The first alignment mark 50A arranged near the third opposing portion 314 can be recognized by a camera through the glass substrate 310. The first alignment mark 50A may be arranged on the surface of the third opposing portion 314. The first alignment mark 50A may also be arranged on the glass substrate 310 on the third opposing portion 314 side. When a light-transmitting insulating layer is arranged on the third opposing portion 314 side, the first alignment mark 50A may be arranged on the light-transmitting insulating layer. When the first alignment mark 50A is arranged near the third opposing portion 314, the distance to the second alignment mark 50B (described later) becomes shorter, thereby improving alignment accuracy.

[0131] 6B , the wiring layer 4 has a second alignment mark 50B. The second alignment mark 50B is provided on the surface of the wiring layer 4. The second alignment mark 50B may be made of the same material as the third-layer line wiring 46. This simplifies the process of forming the alignment mark. However, the second alignment mark 50B may be made of a different material from the third-layer line wiring 46.

[0132] The second alignment mark 50B has a shape corresponding to that of the first alignment mark 50A. The second alignment mark 50B is, for example, a mark made up of four quadrangles, although the shape is not limited to this.

[0133] It is preferable that a plurality of second alignment marks 50B be provided, and more preferably three or more. In this modified example, three second alignment marks 50B are provided. The number of second alignment marks 50B corresponds to the number of first alignment marks 50A.

[0134] In this modification, an alignment step using an alignment mark is performed during the bridge mounting step shown in Fig. 5D. Fig. 6C is a diagram for explaining the alignment step when flip-chip mounting the bridge 31 on the wiring layer 4. Fig. 6C is a top view of the wiring layer 4 and the bridge 31 arranged on the wiring layer 4. Specifically, it is a diagram when Fig. 5D is viewed from the top to the bottom of the paper.

[0135] At least a portion of the bridge 31, from the second opposing portion 313 to the third opposing portion 314, is made of a light-transmitting material. The glass substrate 310 of the bridge 31 is a light-transmitting material. In this modification, the bridge insulating layer 312 is made of a light-transmitting material. Specifically, the bridge insulating layer 312 is preferably made of a light-transmitting resin material or a light-transmitting inorganic material. The light-transmitting resin material is not particularly limited as long as it is light-transmitting, and examples thereof include epoxy, polyimide, polybenzoxazole, and benzocyclobutene. Particles may be dispersed in these resins as long as light transmittance is ensured. The material of the particles is not particularly limited, and examples thereof include silica, alumina, barium sulfate, talc, aluminum nitride, silicon nitride, and silicon carbide. The light-transmitting inorganic material is not particularly limited, and examples thereof include silicon oxide, silicon nitride, silicon carbonitride, and aluminum oxide. In this modification, the surface of the wiring layer 4 can be seen through the bridge 31 , except for the wiring portions such as the bridge wiring 311 provided on the bridge 31 .

[0136] The second alignment mark 50B arranged on the wiring layer 4 can be confirmed by a camera via the bridge 31. Furthermore, when the first alignment mark 50A is arranged near the third opposing portion 314, the first alignment mark 50A arranged near the third opposing portion 314 can also be confirmed by a camera via the glass substrate 310 of the bridge 31.

[0137] 6C , the first alignment mark 50A of the bridge 31 is aligned with the second alignment mark 50B of the wiring layer 4, thereby accurately aligning the position and rotation direction of the bridge 31 on the wiring layer 4. After the first alignment mark 50A and the second alignment mark 50B are aligned, flip-chip mounting is performed. With this modification, flip-chip mounting by metal bonding is possible after accurate alignment, so the bridge 31 can be mounted with even higher positional accuracy.

[0138] It is preferable that a plurality of first alignment marks 50A and second alignment marks 50B are provided in order to accurately align the position and rotation direction of bridge 31 on wiring layer 4. More preferably, three or more first alignment marks 50A and second alignment marks 50B are provided. It is preferable that a plurality of first alignment marks 50A are arranged near the outer periphery of bridge 31 in a plan view. When bridge 31 has a rectangular shape in a plan view, it is preferable that alignment marks be provided at two or more, and preferably three or more, of the four corners of the rectangular shape.

[0139] As described above, the glass bridge 31 formed from the glass substrate preferably has the first alignment mark 50A formed as an alignment mark. The first alignment mark 50A may be formed on either the second opposing portion 313 side or the third opposing portion 314 side. If the first alignment mark 50A is formed on the third opposing portion 314 side, it is preferable that the first alignment mark 50A be formed so that it can be recognized through the glass substrate 310 from the second opposing portion 313 side. If the first alignment mark 50A can be observed from the second opposing portion 313 side, the first alignment mark 50A formed on the glass bridge 31 and the second alignment mark 50B formed on the wiring layer 4 can be recognized with a single camera from the second opposing portion 313 side of the glass bridge 31 when performing alignment when mounting the glass bridge 31 on the wiring layer 4. Furthermore, the camera can be used to recognize and correct the position of the glass bridge 31 until it comes into contact with the wiring layer 4, thereby improving the mounting accuracy of the glass bridge 31.

[0140] Even when the first alignment mark 50A is formed on the second opposing portion 313 side, if the first alignment mark 50A and the second alignment mark 50B can be observed simultaneously from the second opposing portion 313 side, then when aligning the glass bridge 31 on the wiring layer 4, the first alignment mark 50A formed on the glass bridge 31 and the second alignment mark 50B formed on the wiring layer 4 can be recognized with a single camera from the second opposing portion 313 side of the glass bridge 31, and further, position recognition and position correction can be performed with the camera until the glass bridge 31 comes into contact with the wiring layer 4, thereby improving the mounting accuracy of the glass bridge 31.

[0141] <Another embodiment> An electronic device 1A according to another embodiment of the present invention will be described with reference to Fig. 7. Fig. 7 is a cross-sectional view of an electronic device according to another embodiment of the present invention. Note that the electronic device 1A has the same basic configuration as the electronic device 1, so only the differences will be described below.

[0142] The electronic device 1A includes a second wiring layer 6 between the electronic component layer 2 and the connection layer 3. Like the wiring layer 4, the second wiring layer 6 includes power supply wiring and ground wiring, which are connected to the power supply line and ground line of the wiring layer 4 via pillars 32, respectively. The second wiring layer 6 includes signal wiring, which, like the bridge wiring 311, is responsible for transmitting signals between the electronic components 20A, 20B, and 20C. This embodiment also provides an electronic device 1 that allows the bridge 31 to be mounted on the wiring layer 4 with high positional accuracy.

[0143] The electronic device of this embodiment includes the following components.

[0144] (1) The electronic device 1 of this embodiment includes a bridge 31 that electrically connects multiple electronic components 20 together, and a wiring layer 4 having wiring, and the bridge 31 is metal-bonded to the wiring layer 4. This makes it possible to provide an electronic device 1 in which the bridge 31 can be mounted on the wiring layer 4 with high positional accuracy.

[0145] (2) The electronic device 1 of (1) includes a plurality of electronic components 20, each of which has a first facing portion 200 facing a bridge 31. The bridge 31 has a second facing portion 313 facing the first facing portion 200 of each of the electronic components 20 and a third facing portion 314 formed on the opposite side of the second facing portion 313. The bridge 31 has a bridge through electrode 315 (bridge through via 315) that penetrates from the second facing portion 313 to the third facing portion 314, and the bridge through electrode 315 (bridge through via 315) is metal-bonded to the wiring layer 4. This shortens the wiring length when electrically connecting the electronic component 20 to another layer via the bridge 31, and also enables the bridge 31 to be mounted with high positional accuracy on the wiring layer 4. The shortened wiring length as described above enables a stable supply of charge to the electronic component 20. For example, the power supply line of the electronic component 20 and the power supply line of the wiring layer 4 can be connected over a short distance. As another example, the ground line 20 of the electronic component and the ground line of the wiring layer 4 can be connected over a short distance.

[0146] (3) In the electronic device 1 of (1) or (2), the bridge 31 further includes bridge wiring 311 that electrically connects the plurality of electronic components 20 to each other. This allows the plurality of electronic components 20 to directly exchange power and information with each other via the bridge wiring 311.

[0147] (4) In the electronic device 1 of (3), the bridge 31 further includes a bridge insulating layer 312 that insulates the bridge wiring 311. This makes it possible to suppress the occurrence of short circuits between the multiple bridge wirings 311 and between the bridge wiring 311 and the through-bridge via 315.

[0148] (5) In the electronic device 1 of (4), the bridge insulating layer 312 is an organic insulating layer. Organic insulating layers formed from resin materials generally have a low relative dielectric constant. Therefore, by using an organic insulating layer as the bridge insulating layer 312, it is possible to further reduce dielectric loss. Furthermore, by using an organic insulating layer, it is possible to increase the thickness of the bridge insulating layer 312 in accordance with an increase in the thickness of the bridge wiring 311, and even in this case, it is possible to reduce manufacturing costs.

[0149] (6) The electronic device 1 of any one of (1) to (4) further includes an electronic component layer 2 having a plurality of electronic components 20, a wiring layer 4 having wiring, and a connection layer 3 having a bridge 31 and electrically connecting the plurality of electronic components 20 to the wiring layer 4. The effects of the present disclosure can also be obtained with an electronic device 1 having such a configuration.

[0150] (7) In the electronic device 1 of (6), the bridge through electrodes 315 (bridge through vias 315) electrically connect the plurality of electronic components 20 to the wiring of the wiring layer 4. This allows the length of the wiring to be shortened when electrically connecting the electronic components 20 to other layers via the bridges 31.

[0151] (8) In the electronic device 1 of (6) to (7), the connection layer 3 has an insulating layer 30 that covers the periphery of the bridge 31, and the insulating layer 30 has connection-layer through-electrodes 32 (pillars 32) formed therein that penetrate from a facing portion (second facing portion 313) facing the electronic component layer 2 to a facing portion (third facing portion 314) facing the wiring layer 4, electrically connecting the electronic component 20 to the wiring of the wiring layer 4. This allows electrical connection between the electronic component 20 and the wiring of the wiring layer 4 in areas other than the bridge 31.

[0152] (9) In the electronic device 1 of (6) to (8), the electronic components 20 are arranged adjacent to each other. This allows the electronic components 20 to be arranged at high density and the electronic components 20 to be connected to each other by bridges 31.

[0153] (10) In the electronic device 1 of (6) to (9), when the electronic component layer 2 and the connection layer 3 are viewed in the stacking direction, the bridge 31 is arranged so as to overlap each of the plurality of electronic components 20. This allows the electronic components 20 to be densely arranged in the electronic component layer 2. Therefore, in an electronic device 1 of specified dimensions, the amount of information that can be processed by the electronic components 20 can be increased.

[0154] (11) In the electronic device 1 of (1) to (10), the multiple electronic components 20 include at least a first electronic component 20A, a second electronic component 20B, and a third electronic component 20C. The electronic device 1 includes multiple bridges 31, each of which includes a first bridge 31A electrically connecting the first electronic component 20A and the second electronic component 20B to each other and a second bridge 31B electrically connecting the second electronic component 20B and the third electronic component 20C to each other. Conventionally, bridges have been fixed to a wiring layer with adhesive. In this case, the positioning accuracy of the bridge relative to the wiring layer was low. This embodiment enables flip-chip mounting using metal bonding, allowing the bridges 31 to be mounted with high positional accuracy. In particular, when using multiple bridges 31 in an electronic device 1 including three or more electronic components 20, it has been difficult to properly mount the multiple bridges 31 if the positioning accuracy of the multiple bridges 31 is low. This embodiment enables flip-chip mounting using metal bonding, allowing the bridges 31 to be mounted with high positional accuracy.

[0155] (12) In the electronic device 1 of (1) to (11), the bridge 31 is formed of a glass substrate. This makes it possible to provide an electronic device 1 with reduced dielectric loss.

[0156] (13) In the electronic device 1 of (12), the bridge 31 has a second facing portion 313 facing the first facing portion 200 of the plurality of electronic components 20 and a third facing portion 314 formed on the opposite side of the second facing portion 313, at least a portion of the bridge 31 is made of a light-transmitting material from the second facing portion 313 to the third facing portion 314, and the bridge 31 has a first alignment mark 50A. This allows the bridge 31 to be mounted after accurate alignment, thereby enabling the bridge 31 to be mounted with higher positional accuracy.

[0157] (14) In the electronic device 1 of (1) to (13), the bridge 31 is smaller than any of the electronic components 20. This reduces the amount of material used to form the bridge 31, thereby reducing costs.

[0158] (15) A manufacturing method of an electronic device 1 including a bridge 31 that electrically connects multiple electronic components 20 and a wiring layer 4 having wiring, the method including a bridge manufacturing process for manufacturing the bridge 31 and a bridge mounting process for mounting the bridge 31 on the wiring layer 4, the bridge manufacturing process including: a process for preparing a substrate 310; a through-hole forming process for forming through-holes in the substrate 310; a bridge through-electrode forming process for forming bridge through electrodes 315 (bridge through vias 315) in the through-holes; a bump electrode forming process for forming bump electrodes 203 corresponding to the bridge through electrodes 315 (bridge through vias 315); and a cutting process for cutting the substrate 310 to a chip size, and the bridge mounting process metal-bonds the bridge 31 manufactured in the bridge manufacturing process to the wiring layer 4 by flip-chip mounting. This makes it possible to provide an electronic device 1 in which the bridge 31 can be mounted on the wiring layer 4 with high positional accuracy.

[0159] (16) A method for manufacturing the electronic device 1 according to (15), wherein the bridge 31 is formed of a translucent glass substrate and has a first alignment mark 50A (alignment mark), the wiring layer 4 has a second alignment mark 50B corresponding to the first alignment mark 50A of the bridge 31, and the bridge mounting step recognizes the first alignment mark 50A formed on the bridge 31 and the second alignment mark 50B formed on the wiring layer 4 with a single camera, and metal-bonds the bridge 31 and the wiring layer 4 by flip-chip mounting. This makes it possible to mount the bridge 31 after performing accurate alignment, thereby enabling the bridge 31 to be mounted with higher positional accuracy.

[0160] Although the embodiments of the present invention have been described above, the present invention is not limited to the above-described embodiments and various modifications and variations are possible. For example, the components of the respective embodiments can be substituted with each other.

[0161] REFERENCE SIGNS LIST 1 Electronic device 2 Electronic component layer 20 Electronic component 200 First opposing portion 21 Insulating layer 3 Connection layer 30 Insulating layer 31 Bridge 310 Base material 311 Bridge wiring 312 Bridge insulating layer 313 Second opposing portion 314 Third opposing portion 315 Bridge through via (bridge through electrode) 32 Pillar (connection layer through electrode) 4 Wiring layer 42 First layer line wiring 43 First insulating layer 44 Second layer line wiring 45 Second insulating layer 46 Third layer line wiring 47 First layer via wiring 48 Second layer via wiring 49 Bump electrode 5 Substrate 50A First alignment mark (alignment mark) 50B Second alignment mark

Claims

1. An electronic device comprising: a bridge that electrically connects a plurality of electronic components; and a wiring layer having wiring, the bridge being metal-bonded to the wiring layer.

2. The electronic device according to claim 1, comprising a plurality of electronic components, each of the plurality of electronic components having a first opposing portion opposing the bridge, the bridge having a second opposing portion opposing the first opposing portion of the plurality of electronic components and a third opposing portion formed on the opposite side of the second opposing portion, the bridge further having a bridge through electrode penetrating from the second opposing portion to the third opposing portion, and the bridge through electrode being metallically bonded to the wiring layer.

3. The electronic device according to claim 1, wherein the bridge further comprises bridge wiring that electrically connects a plurality of the electronic components to each other.

4. The electronic device according to claim 3, wherein the bridge further comprises a bridge insulating layer for insulating the bridge wiring.

5. The electronic device of claim 4, wherein the bridge insulating layer is an organic insulating layer.

6. The electronic device according to claim 2, comprising: an electronic component layer having the plurality of electronic components; and a connection layer having the bridge and electrically connecting the plurality of electronic components and the wiring layer.

7. The electronic device according to claim 6, wherein the bridge through electrodes electrically connect the plurality of electronic components to the wiring of the wiring layer.

8. The electronic device of claim 6, wherein the connection layer has an insulating layer covering the periphery of the bridge, and a connection layer through electrode is formed in the insulating layer, penetrating from an opposing portion facing the electronic component layer to an opposing portion facing the wiring layer, electrically connecting the electronic component and the wiring of the wiring layer.

9. The electronic device according to claim 6, wherein the plurality of electronic components are arranged adjacent to each other.

10. The electronic device according to claim 6, wherein the bridge is arranged so as to overlap each of the plurality of electronic components when the electronic component layer and the connection layer are viewed in the stacking direction.

11. The electronic device of claim 1, wherein the plurality of electronic components includes at least a first electronic component, a second electronic component, and a third electronic component; the bridges include a first bridge electrically connecting the first electronic component and the second electronic component to each other, and a second bridge electrically connecting the second electronic component and the third electronic component to each other.

12. The electronic device according to claim 1 or 2, wherein the bridge is formed from a glass substrate.

13. The electronic device described in claim 12, wherein the bridge has a second opposing portion opposing the first opposing portions of the plurality of electronic components and a third opposing portion formed on the opposite side of the second opposing portion, at least a portion of the bridge is made of a light-transmitting material from the second opposing portion to the third opposing portion, and the bridge has an alignment mark.

14. The electronic device of claim 1, wherein the bridge is smaller than any of the plurality of electronic components.

15. A method for manufacturing an electronic device comprising a bridge that electrically connects multiple electronic components and a wiring layer having wiring, the method comprising: a bridge manufacturing process for manufacturing the bridge; and a bridge mounting process for mounting the bridge on the wiring layer, the bridge manufacturing process comprising: a process for preparing a substrate; a through hole forming process for forming a through hole in the substrate; a bridge through electrode forming process for forming a bridge through electrode in the through hole; a bump electrode forming process for forming a bump electrode corresponding to the bridge through electrode; and a cutting process for cutting the substrate to a chip size, and the bridge mounting process for metal-bonding the bridge manufactured in the bridge manufacturing process to the wiring layer by flip-chip mounting.

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